It definitely needs to go........ we don't do top knots in this house.
A nice smooth head is what a cocker should have,
I agree with handstripping it out though, it shouldn't take more than 5 minutes to get that out.
Actually I would love to get my hands on that top knot..........
Whatever you decide, he is very handsome (and will remain so, with or without a top knot) and so is his brother.